JAX for inference only on 4090

[modgarden]

A couple things I'd check first. Before rebuilding anything, I'd test one clean baseline with Phi and compare from there. Once you know the plain path

What worked for me was pretty simple. On B200, the easiest win is often to back off the aggressive settings and see whether the problem survives. Once you know the plain path works, then add the faster path back in piece by piece.